re PR fortran/30792 (DATA implied-do substring allowed with -std=f95/f2003)

2018-02-24  Steven G. Kargl <kargl@gcc.gnu.org>

	PR fortran/30792
	* decl.c (gfc_match_data): Check for invalid substring in
	data-implied-do

2018-02-24  Steven G. Kargl <kargl@gcc.gnu.org>

	PR fortran/30792
	* gfortran.dg/data_substring.f90: New test.

From-SVN: r257962

gcc/fortran/ChangeLog

+2018-02-24  Steven G. Kargl <kargl@gcc.gnu.org>
+
+	PR fortran/30792
+	* decl.c (gfc_match_data): Check for invalid substring in
+	data-implied-do
+
 2018-02-23  Steven G. Kargl  <kargl@gcc.gnu.org>
 
 	* intrinsic.texi: Arguments to MATMUL cannot both be rank one.

gcc/fortran/decl.c

@@ -585,6 +585,20 @@ gfc_match_data (void)
       if (m != MATCH_YES)
 	goto cleanup;
 
+      if (new_data->var->iter.var
+	  && new_data->var->iter.var->ts.type == BT_INTEGER
+	  && new_data->var->iter.var->symtree->n.sym->attr.implied_index == 1
+	  && new_data->var->list
+	  && new_data->var->list->expr
+	  && new_data->var->list->expr->ts.type == BT_CHARACTER
+	  && new_data->var->list->expr->ref
+	  && new_data->var->list->expr->ref->type == REF_SUBSTRING)
+	{
+	  gfc_error ("Invalid substring in data-implied-do at %L in DATA "
+		     "statement", &new_data->var->list->expr->where);
+	  goto cleanup;
+	}
+
       m = top_val_list (new_data);
       if (m != MATCH_YES)
 	goto cleanup;

gcc/testsuite/ChangeLog

+2018-02-24  Steven G. Kargl <kargl@gcc.gnu.org>
+
+	PR fortran/30792
+	* gfortran.dg/data_substring.f90: New test.
+
 2018-02-24  Marek Polacek  <polacek@redhat.com>
 
 	PR c++/83692

gcc/testsuite/gfortran.dg/data_substring.f90

+! { dg-do compile }
+! PR fortran/30792
+character string*1025
+integer i
+data (string(i:i),i=1,1025)/1025*'?'/  ! { dg-error "Invalid substring" }
+end